Former Prince George’s County Public Schools executive Andre J. Hornsby was convicted Wednesday of six charges, including fraud and obstruction of justice.

Mr. Hornsby, 54, who was hired as the school system’s chief executive officer in 2003, was found guilty of wire fraud, witness and evidence tampering, and obstruction of justice. He faces a maximum sentence of 90 years. The jury acquitted Hornsby on two other counts and did not reach agreement on 14 charges. He will be sentenced Oct. 20.

“The evidence in this case demonstrated that Andre Hornsby abused his power for financial gain, tampered with witnesses and obstructed a federal investigation,” said Rod J. Rosenstein, U.S. attorney for the District of Maryland. “Public officials must pursue the public interest and not line their own pockets at taxpayer expense.”

Hornsby was accused of steering contracts — with the help of a former employee — to a company that helped school systems by writing applications to secure federal grants, then accepting kickbacks from the contracts.

An initial contract was awarded by the school system to a nonexistent company operated by Hornsby’s associate, Cynthia Joffrion, in December 2003, after five months on the job. Over a two-year period, the school system paid the company more than $120,000.

Videotaped evidence showed Hornsby taking a $1,000 kickback from Miss Joffrion in a Bowie hotel room and agreeing to receive more than $100,000. She has not been charged.

Hornsby also was accused of ordering the purchase of nearly $1 million in software and other materials from a company that employed his live-in girlfriend, Sienna Owens, as a sales representative, then splitting part of the sales commission.

Owens struck a deal to collect half of the commission from the sale and gave Hornsby $10,000 in cash, half of what she was paid. She pleaded guilty in 2006 to a felony tax offense.

Hornsby was indicted in 2006 on corruption and obstruction of justice charges, but U.S. District Judge Roger W. Titus declared a mistrial in November 2007 because jurors were not able to reach a verdict.

Prosecutors also said Hornsby ordered school system employees to destroy back-up computer tapes that contained e-mails that could implicate him in the trial.

The retrial began last month in federal court in Greenbelt. Hornsby faces a maximum sentence of 20 years in prison followed by three years of supervised release for each mail and wire fraud count, and 10 years in prison followed by three years of supervised release for witness tampering and obstruction of justice.

“Mr. Hornsby exploited his position as chief executive officer of the Prince George’s County public schools for his own personal financial gain, which came at the expense of the children he was entrusted to serve,” said FBI Special Agent Amy Jo Lyons, head of the Baltimore office.